Planetary gear train of automatic transmission for vehicle

ABSTRACT

A planetary gear train of an automatic transmission includes: an input shaft; an output shaft; first to fifth planetary gear sets each including first to third rotation elements, fourth to sixth rotation elements, seventh to ninth rotation elements, tenth to twelfth rotation elements, and thirteenth to fifteenth rotational elements; a first shaft connected with the second rotation element and the input shaft; a second shaft connected with the fourteenth rotation element and the output shaft; a third shaft connected with the third and thirteenth rotation elements; a fourth shaft connected with the sixth and fifteenth rotation elements; a fifth shaft connected with the first, eighth, and twelfth rotation elements; a sixth shaft connected with the fourth and ninth rotation elements; a seventh shaft connected with the fifth and eleventh rotation elements; an eighth shaft connected with the seventh rotation element; and a ninth shaft connected with the tenth rotation element.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2017-0058310, filed on May 10, 2017, which isincorporated herein by reference in its entirety.

FIELD

The present disclosure relates to a planetary gear train of an automatictransmission for a vehicle that improves power delivery performance andfuel economy.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

Generally, an automatic transmission achieving more speed stages hasbeen developed to enhance fuel efficiency and drivability.

Such an automatic transmission achieving more speed stages is desired toincrease power performance and driving efficiency for downsizing of anengine. Particularly, a highly efficient multiple-speed transmissionhaving excellent linearity of step ratios closely relates to drivabilityof a vehicle (e.g., acceleration before and after gear shifts as well asrhythmical engine speed).

However, in the automatic transmission, as the number of speed stagesincrease, the number of internal components increase, and as a result,mountability, cost, weight, transmission efficiency, and the like areundermined.

Accordingly, development of a planetary gear train which may achievebetter efficiency with reduced components may be important in order toincrease a fuel efficiency enhancement through the multiple-speedtransmission.

In this background, an eight-speed automatic transmission has beenintroduced recently and a planetary gear train for an automatictransmission enabling more shift-stages has been developed.

However, we have discovered that since a conventional eight-speedautomatic transmission has gear ratio span between 6.5 and 7.5 (gearratio span is a factor for securing linearity of step ratios), powerperformance and fuel economy is not great.

In addition, if an eight-speed automatic transmission has gear ratiospan larger than 9.0, it is hard to secure linearity of step ratios.Therefore, driving efficiency of an engine and drivability of a vehiclemay be deteriorated.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the present disclosureand therefore it may contain information that does not form the priorart that is already known to a person of ordinary skill in the art.

SUMMARY

The present disclosure has been made in an effort to provide a planetarygear train of an automatic transmission for a vehicle having advantagesof improving power delivery performance and fuel economy by achievingten forward speed stages and one reverse speed stage and reducing dragloss of clutches and brakes using five planetary gear sets and sixengaging elements.

An exemplary form of the present disclosure provides a planetary geartrain of an automatic transmission for a vehicle having furtheradvantages of improving torque delivery efficiency and durability byusing a planetary gear set of an output side in torque parallel type andreducing torque share with each planetary gear set and each engagingelement.

Yet another form of the present disclosure provides a high-efficiencyplanetary gear train of an automatic transmission for a vehicle havingfurther advantages of increasing flexibility of output gear ratios andimproving linearity of step ratios by using five planetary gear sets forachieving ten forward speed stages and one reverse speed stage.

A planetary gear train of an automatic transmission for a vehicleaccording to an exemplary form of the present disclosure may include: aninput shaft receiving torque of an engine; an output shaft outputtingtorque; a first planetary gear set including first, second, and thirdrotation elements; a second planetary gear set including fourth, fifth,and sixth rotation elements; a third planetary gear set includingseventh, eighth, and ninth rotation elements; a fourth planetary gearset including tenth, eleventh, and twelfth rotation elements; a fifthplanetary gear set including thirteenth, fourteenth, and fifteenthrotational elements; a first shaft connected with the second rotationelement and the input shaft; a second shaft connected with thefourteenth rotation element and the output shaft; a third shaftconnected with the third rotation element and the thirteenth rotationelement; a fourth shaft connected with the sixth rotation element andthe fifteenth rotation element; a fifth shaft connected with the firstrotation element, the eighth rotation element, and the twelfth rotationelement; a sixth shaft connected with the fourth rotation element andthe ninth rotation element; a seventh shaft connected with the fifthrotation element and the eleventh rotation element; an eighth shaftconnected with the seventh rotation element; and a ninth shaft connectedwith the tenth rotation element.

The planetary gear train may further include: six engaging elementsselectively connecting, among the nine shafts, any one shaft withanother shaft, or a corresponding shaft selected from the nine shaftswith a transmission housing, wherein any one of forward speed stages ora reverse speed stage is achieved by operating three engaging elementsamong the six engaging elements.

The six engaging elements may include: three clutches, any one thereofconnecting any two shafts among the nine shafts; and three brakes, anyone thereof selectively connecting the corresponding shaftselected fromthe nine shafts to the transmission housing, wherein that thecorresponding shaft is not connected with the input shaft or the outputshaft.

The first planetary gear set may be configured to be locked-up byselectively connecting any two shafts among the first shaft, the thirdshaft, and the fifth shaft with each other through any one clutch amongthe three clutches.

In one aspect, the six engaging elements may include: a first clutchdisposed between the second shaft and the sixth shaft; a second clutchdisposed between the first shaft and the fifth shaft; a third clutchdisposed between the third shaft and the sixth shaft; a first brakedisposed between the seventh shaft and the transmission housing; asecond brake disposed between the eighth shaft and the transmissionhousing; and a third brake disposed between the ninth shaft and thetransmission housing.

In another aspect, the six engaging elements may include: a first clutchdisposed between the second shaft and the sixth shaft; a second clutchdisposed between the first shaft and the third shaft; a third clutchdisposed between the third shaft and the sixth shaft; a first brakedisposed between the seventh shaft and the transmission housing; asecond brake disposed between the eighth shaft and the transmissionhousing; and a third brake disposed between the ninth shaft and thetransmission housing.

In other aspect, the six engaging elements may include: a first clutchdisposed between the second shaft and the sixth shaft; a second clutchdisposed between the third shaft and the fifth shaft; a third clutchdisposed between the third shaft and the sixth shaft; a first brakedisposed between the seventh shaft and the transmission housing; asecond brake disposed between the eighth shaft and the transmissionhousing; and a third brake disposed between the ninth shaft and thetransmission housing.

The first, second, and third rotational elements may be a first sungear, a first planet carrier, and a first ring gear respectively, thefourth, fifth, and sixth rotational elements may be a second sun gear, asecond planet carrier, and a second ring gear respectively, the seventh,eighth, and ninth rotational elements may be a third sun gear, a thirdplanet carrier, and a third ring gear respectively, the tenth, eleventh,and twelfth rotational elements may be a fourth sun gear, a fourthplanet carrier, and a fourth ring gear respectively, and the thirteenth,fourteenth, and fifteenth rotational elements may be a fifth sun gear, afifth planet carrier, and a fifth ring gear respectively.

The first, second, third, fourth, and fifth planetary gear sets may bedisposed in a sequence of the first, third, fourth, second, and fifthplanetary gear sets.

A planetary gear train of an automatic transmission for a vehicleaccording to another exemplary form of the present disclosure mayinclude: an input shaft receiving torque of an engine; an output shaftoutputting torque; a first planetary gear set including first, second,and third rotation elements; a second planetary gear set includingfourth, fifth, and sixth rotation elements; a third planetary gear setincluding seventh, eighth, and ninth rotation elements; a fourthplanetary gear set including tenth, eleventh, and twelfth rotationelements; a fifth planetary gear set including thirteenth, fourteenth,and fifteenth rotational elements; a first shaft connected with thesecond rotation element and the input shaft; a second shaft connectedwith the fourteenth rotation element and the output shaft; a third shaftconnected with the third rotation element and the thirteenth rotationelement; a fourth shaft connected with the sixth rotation element andthe fifteenth rotation element; a fifth shaft connected with the firstrotation element, the eighth rotation element, and the twelfth rotationelement; a sixth shaft connected with the fourth rotation element andthe ninth rotation element; and a plurality of shafts configured toselectively and respectively connect a transmission housing tocorresponding rotation elements selected from the rotation elementsselected from the second, third, and fourth planetary gear sets, whereinthe selected corresponding rotation elements are not connected to any ofthe first to sixth shafts.

The plurality of shafts may include: a seventh shaft connected with thefifth rotation element and the eleventh rotation element; an eighthshaft connected with the seventh rotation element; and a ninth shaftconnected with the tenth rotation element.

The planetary gear train may further include: three clutches, any onethereof connecting any two shafts among the nine shafts; and threebrakes, any one thereof selectively connecting the transmission housingto a corresponding shaft selected from the nine shafts, wherein theselected corresponding shaft is not connected with the input shaft orthe output shaft.

In one aspect, the three clutches may include: a first clutch disposedbetween the second shaft and the sixth shaft; a second clutch disposedbetween the first shaft and the fifth shaft; and a third clutch disposedbetween the third shaft and the sixth shaft.

The three brakes may include: a first brake disposed between the seventhshaft and the transmission housing; a second brake disposed between theeighth shaft and the transmission housing; and a third brake disposedbetween the ninth shaft and the transmission housing.

In another aspect, the three clutches may include: a first clutchdisposed between the second shaft and the sixth shaft; a second clutchdisposed between the first shaft and the third shaft; and a third clutchdisposed between the third shaft and the sixth shaft.

The three brakes may include: a first brake disposed between the seventhshaft and the transmission housing; a second brake disposed between theeighth shaft and the transmission housing; and a third brake disposedbetween the ninth shaft and the transmission housing.

In other aspect, the three clutches may include: a first clutch disposedbetween the second shaft and the sixth shaft; a second clutch disposedbetween the third shaft and the fifth shaft; and a third clutch disposedbetween the third shaft and the sixth shaft.

The three brakes may include: a first brake disposed between the seventhshaft and the transmission housing; a second brake disposed between theeighth shaft and the transmission housing; and a third brake disposedbetween the ninth shaft and the transmission housing.

A planetary gear train of an automatic transmission for a vehicleaccording to other exemplary form of the present disclosure may include:an input shaft receiving torque of an engine; an output shaft outputtingtorque; a first planetary gear set including first, second, and thirdrotation elements; a second planetary gear set including fourth, fifth,and sixth rotation elements; a third planetary gear set includingseventh, eighth, and ninth rotation elements; a fourth planetary gearset including tenth, eleventh, and twelfth rotation elements; a fifthplanetary gear set including thirteenth, fourteenth, and fifteenthrotational elements; a first shaft connected with the second rotationelement and the input shaft; a second shaft connected with thefourteenth rotation element and the output shaft; a third shaftconnected with the third rotation element and the thirteenth rotationelement; a fourth shaft connected with the sixth rotation element andthe fifteenth rotation element; a fifth shaft connected with the firstrotation element, the eighth rotation element, and the twelfth rotationelement; a sixth shaft connected with the fourth rotation element andthe ninth rotation element; and seventh, eighth, and ninth shaftsconfigured to selectively and respectively connect a transmissionhousing to corresponding rotation elements selected from the rotationelements of the second, third, and fourth planetary gear sets, whereinthe corresponding rotation elements are not connected to any one of thefirst to sixth shafts.

In one aspect, the second shaft and the sixth shaft, the first shaft andthe fifth shaft, and the third shaft and the sixth shaft may beselectively and respectively connected with each other through clutches,the seventh shaft may be connected with the fifth rotation element andthe eleventh rotation element, the eighth shaft may be connected withthe seventh rotation element, and the ninth shaft may be connected withthe tenth rotation element.

In another aspect, the second shaft and the sixth shaft, the first shaftand the third shaft, and the third shaft and the sixth shaft may beselectively and respectively connected with each other through clutches,the seventh shaft may be connected with the fifth rotation element andthe eleventh rotation element, the eighth shaft may be connected withthe seventh rotation element, and the ninth shaft may be connected withthe tenth rotation element.

In other aspect, the second shaft and the sixth shaft, the third shaftand the fifth shaft, and the third shaft and the sixth shaft may beselectively and respectively connected with each other through clutches,the seventh shaft may be connected with the fifth rotation element andthe eleventh rotation element, the eighth shaft may be connected withthe seventh rotation element, and the ninth shaft may be connected withthe tenth rotation element.

The first, second, and third rotational elements may be a first sungear, a first planet carrier, and a first ring gear respectively, thefourth, fifth, and sixth rotational elements may be a second sun gear, asecond planet carrier, and a second ring gear respectively, the seventh,eighth, and ninth rotational elements may be a third sun gear, a thirdplanet carrier, and a third ring gear respectively, the tenth, eleventh,and twelfth rotational elements may be a fourth sun gear, a fourthplanet carrier, and a fourth ring gear respectively, and the thirteenth,fourteenth, and fifteenth rotational elements may be a fifth sun gear, afifth planet carrier, and a fifth ring gear respectively.

According to exemplary forms of the present disclosure, ten forwardspeed stages and one reverse speed stage may be achieved by combiningfive planetary gear sets being simple planetary gear sets with sixengaging elements.

In addition, since gear ratio span greater than 8.8 is secured, drivingefficiency of the engine increases. In addition, since linearity of stepratios can be secured due to multiple speed stages, drivability such asacceleration before and after gear shifts, rhythmical engine speed, andso on may be improved.

In addition, since ten forward speed stages and one reverse speed stageare achieved by using five planetary gear sets with reduced engagingelements, drag loss caused by clutches and brakes may be reduced andthus power delivery efficiency and fuel economy may be improved.

In addition, since a planetary gear set of an output side in torqueparallel type is used and torque is evenly shared to each planetary gearset and each engaging element, torque delivery efficiency and durabilitymay be improved.

In addition, since five planetary gear sets are used to achieve tenforward speed stages and one reverse speed stage, flexibility of outputgear ratios may be increased and linearity of step ratios may beimproved.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

In order that the disclosure may be well understood, there will now bedescribed various forms thereof, given by way of example, referencebeing made to the accompanying drawings, in which:

FIG. 1 is a schematic diagram of a planetary gear train according to afirst exemplary form of the present disclosure;

FIG. 2 is an operation chart of engaging elements at each speed stage inthe planetary gear train according to a first exemplary form of thepresent disclosure;

FIG. 3 is a schematic diagram of a planetary gear train according to asecond exemplary form of the present disclosure; and

FIG. 4 is a schematic diagram of a planetary gear train according to thethird exemplary form of the present disclosure.

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses. Itshould be understood that throughout the drawings, correspondingreference numerals indicate like or corresponding parts and features.

However, parts which are not related with the description are omittedfor clearly describing the exemplary forms of the present disclosure.

In the following description, dividing names of components into first,second, and the like is to divide the names because the names of thecomponents are the same as each other and an order thereof is notparticularly limited.

Further, as used herein, description of elements being “fixedly”connected or interconnected includes elements that are directlyconnected, i.e. one element directly connected to another element forrotation therewith.

FIG. 1 is a schematic diagram of a planetary gear train in a firstexemplary form of the present disclosure.

Referring to FIG. 1, a planetary gear train includes: first, second,third, fourth, and fifth planetary gear sets PG1, PG2, PG3, PG4, and PG5disposed on the same axis; an input shaft IS; an output shaft OS; nineshafts TM1 to TM9 connected to at least one rotation element of thefirst, second, third, fourth, and fifth planetary gear sets PG1, PG2,PG3, PG4, and PG5; engaging elements including three clutches C1 to C3and three brakes B1 to B3; and a transmission housing H.

Torque input from an engine to the input shaft IS is changed bycooperation of the first, second, third, fourth, and fifth planetarygear sets PG1, PG2, PG3, PG4, and PG5, and the changed torque is outputthrough the output shaft OS.

In one form of the present disclosure, the planetary gear sets aredisposed in a sequence of the first, third, fourth, second, and fifthplanetary gear sets PG1, PG3, PG4, PG2, and PG5 from an engine side.

The input shaft IS is an input member and torque from a crankshaft ofthe engine is torque-converted through a torque converter to be inputinto the input shaft IS.

The output shaft OS is an output member, as disposed on the same axiswith the input shaft IS, and transmits driving torque to a driving wheelthrough a differential apparatus.

The first planetary gear set PG1 is a single pinion planetary gear setand includes a first sun gear S1 as a first rotation element N1, a firstplanet carrier PC1 as a second rotation element N2 rotatably supportinga plurality of first pinion gears P1 evenly disposed on and externallyengaged with an exterior circumference of the first sun gear S1, and afirst ring gear R1 as a third rotation element N3 internally engagedwith the plurality of first pinion gears P1 and operably connected withthe first sun gear S1.

The second planetary gear set PG2 is a single pinion planetary gear setand includes a second sun gear S2 as a fourth rotation element N4, asecond planet carrier PC2 as a fifth rotation element N5 rotatablysupporting a plurality of second pinion gears P2 evenly disposed on andexternally engaged with an exterior circumference of the second sun gearS2, and a second ring gear R2 as a sixth rotation element N6 internallyengaged with the plurality of second pinion gears P2 and operablyconnected with the second sun gear S2.

The third planetary gear set PG3 is a single pinion planetary gear setand includes a third sun gear S3 as a seventh rotation element N7, athird planet carrier PC3 as an eighth rotation element N8 rotatablysupporting a plurality of third pinion gears P3 evenly disposed on andexternally engaged with an exterior circumference of the third sun gearS3, and a third ring gear R3 as a ninth rotation element N9 internallyengaged with the plurality of third pinion gears P3 and operablyconnected with the third sun gear S3.

The fourth planetary gear set PG4 is a single pinion planetary gear setand includes a fourth sun gear S4 as a tenth rotation element N10, afourth planet carrier PC4 as an eleventh rotation element N11 rotatablysupporting a plurality of fourth pinion gears P4 evenly disposed on andexternally engaged with an exterior circumference of the fourth sun gearS4, and a fourth ring gear R4 as a twelfth rotation element N12internally engaged with the plurality of fourth pinion gears P4 andoperably connected with the fourth sun gear S4.

The fifth planetary gear set PG5 is a single pinion planetary gear setand includes a fifth sun gear S5 as a thirteenth rotation element N13, afifth planet carrier PC5 as a fourteenth rotation element N14 rotatablysupporting a plurality of fifth pinion gears P5 evenly disposed on andexternally engaged with an exterior circumference of the fifth sun gearS5, and a fifth ring gear R5 as a fifteenth rotation element N15internally engaged with the plurality of fifth pinion gears P5 andoperably connected with the fifth sun gear S5.

The first rotation element N1 is directly connected with the eighthrotation element N8 and the twelfth rotation element N12, the thirdrotation element N3 is directly connected with the thirteenth rotationelement N13, the fourth rotation element N4 is directly connected withthe ninth rotation element N9, the fifth rotation element N5 is directlyconnected with the eleventh rotation element N11, and the sixth rotationelement N6 is directly connected with the fifteenth rotation element N15such that the first, second, third, fourth, and fifth planetary gearsets PG1, PG2, PG3, PG4, and PG5 operate each other through nine shaftsTM1 to TM9.

The nine shafts TM1 to TM9 will be described in further detail.

Some of the nine shafts TM1 to TM9 directly connect a plurality ofrotation elements among the rotation elements of the planetary gear setsPG1, PG2, PG3, PG4, and PG5 with each other. The nine shafts may berotation members that are connected to any one rotation element of therotation elements of the planetary gear sets PG1, PG2, PG3, PG4, andPG5, and rotate with the any one rotation element to transmit torque.The rotation members that selectively connect any one rotation elementwith the transmission housing H may be fixed members that directly andfixedly connect any one rotation element to the transmission housing H.

The first shaft TM1 is connected, and preferably fixedly connected, withthe second rotation element N2 (first planet carrier PC1) and isdirectly connected with the input shaft IS so as to be continuouslyoperated as an input element.

The second shaft TM2 is connected, and preferably fixedly connected,with the fourteenth rotation element N14 (fifth planet carrier PC5) andis directly connected with the output shaft OS so as to be continuouslyoperated as an output element.

The third shaft TM3 is connected, and preferably fixedly connected, withthe third rotation element N3 (first ring gear R1) and the thirteenthrotation element N13 (fifth sun gear S5).

The fourth shaft TM4 is connected, and preferably fixedly connected,with the sixth rotation element N6 (second ring gear R2) and thefifteenth rotation element N15 (fifth ring gear R3).

The fifth shaft TM5 is connected, and preferably fixedly connected, withthe first rotation element N1 (first sun gear S1), the eighth rotationelement N8 (third planet carrier PC3), and the twelfth rotation elementN12 (fourth ring gear R4).

The sixth shaft TM6 is connected, and preferably fixedly connected, withthe fourth rotation element N4 (second sun gear S2) and the ninthrotation element N9 (third ring gear R3).

The seventh shaft TM7 is connected, and preferably fixedly connected,with the fifth rotation element N5 (second planet carrier PC2) and theeleventh rotation element N11 (third planet carrier PC3).

The eighth shaft TM8 is connected, and preferably fixedly connected,with the seventh rotation element N7 (third sun gear S3).

The ninth shaft TM9 is connected, and preferably fixedly connected, withthe tenth rotation element N10 (fourth sun gear S4).

Here, the first shaft TM1 is selectively connected with the fifth shaftTM5, and the sixth shaft TM6 is selectively connected respectively tothe second shaft TM2 and the third shaft TM3.

In addition, the seventh shaft TM7, the eighth shaft TM8, and the ninthshaft TM9 are selectively and respectively connected to the transmissionhousing H so as to be operated as selective fixed elements.

Three clutches C1, C2, and C3 that are engaging elements are disposed atportions at which any two shafts among the nine shafts TM1 to TM9including the input shaft IS and the output shaft OS are selectivelyconnected with each other.

In addition, three brakes B1, B2, and B3 that are engaging elements aredisposed at portions at which any one shaft among the nine shafts TM1 toTM9 is selectively connected with the transmission housing H.

Arrangement of the six engaging elements (three clutches C1 to C3 andthree brakes B1 to B3) will be described in detail.

The first clutch C1 is disposed between the second shaft TM2 and thesixth shaft TM6 and selectively connects the second shaft TM2 with thesixth shaft TM6.

The second clutch C2 is disposed between the first shaft TM1 and thefifth shaft TM5 and selectively connects the first shaft TM1 with thefifth shaft TM5.

The third clutch C3 is disposed between the third shaft TM3 and thesixth shaft TM6 and selectively connects the third shaft TM3 with thesixth shaft TM6.

The first brake B1 is disposed between the seventh shaft TM7 and thetransmission housing H and selectively connects and fixes the seventhshaft TM7 to the transmission housing H.

The second brake B2 is disposed between the eighth shaft TM8 and thetransmission housing H and selectively connects and fixes the eighthshaft TM8 to the transmission housing H.

The third brake B3 is disposed between the ninth shaft TM9 and thetransmission housing H and selectively connects and fixes the ninthshaft TM9 to the transmission housing H.

In the first exemplary form of the present disclosure, the second clutchC2 is configured to selectively connect the first shaft TM1 with thefifth shaft TM5. Here, the second clutch C2 selectively connects any twoshafts among the first, second, and third rotation elements N1, N2, andN3 of the first planetary gear set PG1 such that all the rotationelements of the first planetary gear set PG1 integrally rotate. That is,the second clutch C2 selectively connects any two shafts among the firstshaft TM1, the third shaft TM3, and the fifth shaft TM5 with each otherso as for the first planetary gear set PG1 to be locked-up.

The engaging elements including the first, second, and third clutchesC1, C2, and C3 and the first, second, and third brakes B1, B2, and B3may be multi-plates friction elements of wet type that are operated byhydraulic pressure. Multi-plates friction elements of wet type aremainly used as the engaging elements, but dog clutches, electricclutches, or magnetic clutches that can be operated by electric signalfrom an electric control unit can be used as the engaging elements.

FIG. 2 is an operation chart of engaging elements at each speed stage inthe planetary gear train according to the first exemplary form of thepresent disclosure.

Referring to FIG. 2, three engaging elements among the first, second,and third clutches C1, C2, and C3 and the first, second, and thirdbrakes B1, B2, and B3 are operated at each speed stage in the planetarygear train according to the first exemplary form of the presentdisclosure.

The first and second clutches C1 and C2 and the first brake B1 areoperated at a first forward speed stage D1.

In a state that the second shaft TM2 is connected with the sixth shaftTM6 by operation of the first clutch C1, and the first shaft TM1 isconnected with the fifth shaft TM5 by operation of the second clutch C2such that the first planetary gear set PG1 is locked-up, torque of theinput shaft IS is input to the first shaft TM1.

At this state, the seventh shaft TM7 is operated as the fixed element byoperation of the first brake B1. Therefore, the torque of the inputshaft IS is shifted into the first forward speed stage, and the firstforward speed stage is output through the output shaft OS connected withthe second shaft TM2.

The first clutch C1 and the first and third brakes B1 and B3 areoperated at a second forward speed stage D2.

In a state that the second shaft TM2 is connected with the sixth shaftTM6 by operation of the first clutch C1, the torque of the input shaftIS is input to the first shaft TM1.

At this state, the seventh shaft TM7 and the ninth shaft TM9 areoperated as the fixed elements by operation of the first and thirdbrakes B1 and B3. Therefore, the torque of the input shaft IS is shiftedinto the second forward speed stage, and the second forward speed stageis output through the output shaft OS connected with the second shaftTM2.

The first clutch C1 and the second and third brakes B2 and B3 areoperated at a third forward speed stage D3.

In a state that the second shaft TM2 is connected with the sixth shaftTM6 by operation of the first clutch C1, the torque of the input shaftIS is input to the first shaft TM1.

At this state, the eighth shaft TM8 and the ninth shaft TM9 are operatedas the fixed elements by operation of the second and third brakes B2 andB3. Therefore, the torque of the input shaft IS is shifted into thethird forward speed stage, and the third forward speed stage is outputthrough the output shaft OS connected with the second shaft TM2.

The second clutch C2 and the second and third brakes B2 and B3 areoperated at a fourth forward speed stage D4.

In a state that the first shaft TM1 is connected with the fifth shaftTM5 by operation of the second clutch C2 such that the first planetarygear set PG1 is locked-up, the torque of the input shaft IS is input tothe first shaft TM1.

At this state, the eighth shaft TM8 and the ninth shaft TM9 are operatedas the fixed elements by operation of the second and third brakes B2 andB3. Therefore, the torque of the input shaft IS is shifted into thefourth forward speed stage, and the fourth forward speed stage is outputthrough the output shaft OS connected with the second shaft TM2.

The second and third clutches C2 and C3 and the third brake B3 areoperated at a fifth forward speed stage D5.

In a state that the first shaft TM1 is connected with the fifth shaftTM5 by operation of the second clutch C2 such that the first planetarygear set PG1 is locked-up, and the third shaft TM3 is connected with thesixth shaft TM6 by operation of the third clutch C3, the torque of theinput shaft IS is input to the first shaft TM1.

At this state, the ninth shaft TM9 is operated as the fixed element byoperation of the third brake B3. Therefore, the torque of the inputshaft IS is shifted into the fifth forward speed stage, and the fifthforward speed stage is output through the output shaft OS connected withthe second shaft TM2.

The first and second clutches C1 and C2 and the third brake B3 areoperated at a sixth forward speed stage D6.

In a state that the second shaft TM2 is connected with the sixth shaftTM6 by operation of the first clutch C1, and the first shaft TM1 isconnected with the fifth shaft TM5 by operation of the second clutch C2such that the first planetary gear set PG1 is locked-up, the torque ofthe input shaft IS is input to the first shaft TM1.

At this state, the ninth shaft TM9 is operated as the fixed element byoperation of the third brake B3. Therefore, the torque of the inputshaft IS is shifted into the sixth forward speed stage, and the sixthforward speed stage is output through the output shaft OS connected withthe second shaft TM2.

The first and third clutches C1 and C3 and the third brake B3 areoperated at a seventh forward speed stage D7.

In a state the second shaft TM2 is connected with the sixth shaft TM6 byoperation of the first clutch C1 and the third shaft TM3 is connectedwith the sixth shaft TM6 by operation of the third clutch C3, the torqueof the input shaft IS is input to the first shaft TM1.

At this state, the ninth shaft TM9 is operated as the fixed element byoperation of the third brake B3. Therefore, the torque of the inputshaft IS is shifted into the seventh forward speed stage, and theseventh forward speed stage is output through the output shaft OSconnected with the second shaft TM2.

The first, second, and third clutches C1, C2, and C3 are operated at aneighth forward speed stage D8.

In a state that the second shaft TM2 is connected with the sixth shaftTM6 by operation of the first clutch C1, the first shaft TM1 isconnected with the fifth shaft TM5 by operation of the second clutch C2such that the first planetary gear set PG1 is locked-up, and the thirdshaft TM3 is connected with the sixth shaft TM6 by operation of thethird clutch C3, the torque of the input shaft IS is input to the firstshaft TM1.

In this case, the first, second, third, fourth, and fifth planetary gearsets PG1, PG2, PG3, PG4, and PG5 become lock-up states. Therefore, thetorque of the input shaft IS is output through the output shaft OSconnected with the second shaft TM2 without speed change.

The first and third clutches C1 and C3 and the second brake B2 areoperated at a ninth forward speed stage D9.

In a state that the second shaft TM2 is connected with the sixth shaftTM6 by operation of the first clutch C1 and the third shaft TM3 isconnected with the sixth shaft TM6 by operation of the third clutch C3,the torque of the input shaft IS is input to the first shaft TM1.

At this state, the eighth shaft TM8 is operated as the fixed element byoperation of the second brake B2. Therefore, the torque of the inputshaft IS is shifted into the ninth forward speed stage, and the ninthforward speed stage is output through the output shaft OS connected withthe second shaft TM2.

The first and second clutches C1 and C2 and the second brake B2 areoperated at a tenth forward speed stage D10.

In a state that the second shaft TM2 is connected with the sixth shaftTM6 by operation of the first clutch C1, and the first shaft TM1 isconnected with the fifth shaft TM5 by operation of the second clutch C2such that the first planetary gear set PG1 is locked-up, the torque ofthe input shaft IS is input to the first shaft TM1.

At this state, the eighth shaft TM8 is operated as the fixed element byoperation of the second brake B2. Therefore, the torque of the inputshaft IS is shifted into the tenth forward speed stage, and the tenthforward speed stage is output through the output shaft OS connected withthe second shaft TM2.

The second clutch C2 and the first and second brakes B1 and B2 areoperated at a reverse speed stage REV.

In a state that the first shaft TM1 is connected with the fifth shaftTM5 by operation of the second clutch C2 such that the first planetarygear set PG1 is locked-up, the torque of the input shaft IS is input tothe first shaft TM1.

At this state, the seventh shaft TM7 and the eighth shaft TM8 areoperated as the fixed elements by operation of the first and secondbrakes B1 and B2. Therefore, the torque of the input shaft IS is shiftedinto the reverse speed stage, and the reverse speed stage is outputthrough the output shaft OS connected with the second shaft TM2.

FIG. 3 is a schematic diagram of a planetary gear train according to asecond exemplary form of the present disclosure.

Referring to FIG. 1 and FIG. 3, the second clutch C2 that is lock-upmeans of the first planetary gear set PG1 in the planetary gear trainaccording to the first exemplary form of the present disclosure isdisposed between the first shaft TM1 and the fifth shaft TM5, but in theplanetary gear train according to the second exemplary form of thepresent disclosure, the second clutch C2 is disposed between the firstshaft TM1 and the third shaft TM3 and selectively connects the firstshaft TM1 with the third shaft TM3.

The arrangement of the second clutch C2 according to the secondexemplary form differs from that according to the first exemplary form,but connections of the nine shafts TM1 to TM9, two clutches C1 and C3,and the three brakes B1 to B3 according to the second exemplary form arethe same as those according to the first exemplary form. Therefore,operations and effects of the planetary gear train according to thesecond exemplary form are the same as those according to the firstexemplary form.

FIG. 4 is a schematic diagram of a planetary gear train according to thethird exemplary form of the present disclosure.

Referring to FIG. 1 and FIG. 4, the second clutch C2 that is lock-upmeans of the first planetary gear set PG1 in the planetary gear trainaccording to the first exemplary form of the present disclosure isdisposed between the first shaft TM1 and the fifth shaft TM5, but in theplanetary gear train according to the third exemplary form of thepresent disclosure, the second clutch C2 is disposed between the thirdshaft TM3 and the fifth shaft TM5 and selectively connects the thirdshaft TM3 with the fourth shaft TM4.

The arrangement of the second clutch C2 according to the third exemplaryform differs from that according to the first exemplary form, butconnections of the nine shafts TM1 to TM9, two clutches C1 and C3, andthe three brakes B1 to B3 according to the third exemplary form are thesame as those according to the first exemplary form. Therefore,operations and effects of the planetary gear train according to thethird exemplary form are the same as those according to the firstexemplary form.

According to the first to third exemplary forms of the presentdisclosure, ten forward speed stages and one reverse speed stage may beachieved by using five planetary gear sets PG1, PG2, PG3, PG4, and PG5and six engaging elements including three clutches C1, C2, and C3 andthree brakes B1, B2, and B3.

In addition, since gear ratio span is secured to be greater than 8.8,driving efficiency of the engine may be increased. In addition, sincelinearity of step ratios can be secured due to multiple speed stages,drivability such as acceleration before and after gear shifts,rhythmical engine speed, and so on may be improved.

In addition, since ten forward speed stages and one reverse speed stageare achieved with reduced number of engaging elements, drag loss ofclutches and brakes may be reduced and power delivery efficiency andfuel economy may be improved.

In addition, since a planetary gear set of an output side in torqueparallel type is used, and torque is evenly shared to each planetarygear set and each engaging element, and thus torque delivery efficiencyand durability may be improved.

In addition, since five planetary gear sets are used to achieve tenforward speed stages and one reverse speed stage, flexibility of outputgear ratios may be increased and linearity of step ratios may beimproved.

While this present disclosure has been described in connection with whatis presently considered to be practical exemplary forms, it is to beunderstood that the present disclosure is not limited to the disclosedforms, but, on the contrary, is intended to cover various modificationsand equivalent arrangements included within the spirit and scope of thepresent disclosure.

DESCRIPTION OF SYMBOLS

-   -   PG1, PG2, PG3, PG4, PG5: first, second, third, fourth, and fifth        planetary gear sets    -   S1, S2, S3, S4, S5: first, second, third, fourth, and fifth sun        gears    -   PC1, PC2, PC3, PC4, PC5: first, second, third, fourth, and fifth        planet carriers    -   R1, R2, R3, R4, R5: first, second, third, fourth, and fifth ring        gears    -   C1, C2, C3: first, second, and third clutches    -   B1, B2, B3: first, second, and third brakes    -   IS: input shaft OS: output shaft    -   TM1, TM2, TM3, TM4, TM5, TM6, TM7, TM8, TM9: first, second,        third, fourth, fifth, sixth, seventh, eighth, and ninth shafts

What is claimed is:
 1. A planetary gear train of an automatictransmission for a vehicle, comprising: an input shaft configured toreceive a torque from an engine; an output shaft configured to output atorque; a first planetary gear set including first, second, and thirdrotation elements; a second planetary gear set including fourth, fifth,and sixth rotation elements; a third planetary gear set includingseventh, eighth, and ninth rotation elements; a fourth planetary gearset including tenth, eleventh, and twelfth rotation elements; a fifthplanetary gear set including thirteenth, fourteenth, and fifteenthrotational elements; a first shaft connected with the second rotationelement and the input shaft; a second shaft connected with thefourteenth rotation element and the output shaft; a third shaftconnected with the third rotation element and the thirteenth rotationelement; a fourth shaft connected with the sixth rotation element andthe fifteenth rotation element; a fifth shaft connected with the firstrotation element, the eighth rotation element, and the twelfth rotationelement; a sixth shaft connected with the fourth rotation element andthe ninth rotation element; a seventh shaft connected with the fifthrotation element and the eleventh rotation element; an eighth shaftconnected with the seventh rotation element; and a ninth shaft connectedwith the tenth rotation element.
 2. The planetary gear train of claim 1,further comprising six engaging elements configured to selectivelyconnect, among the nine shafts, any one shaft with another shaft or acorresponding shaft selected from the nine shafts with a transmissionhousing, wherein any one of forward speed stages or a reverse speedstage is achieved by operating three engaging elements among the sixengaging elements.
 3. The planetary gear train of claim 2, wherein thesix engaging elements comprise: three clutches, any one thereofconfigured to connect any two shafts selected from the nine shafts; andthree brakes, any one thereof configured to selectively connect thecorresponding shaft selected from the nine shafts to the transmissionhousing, wherein the corresponding shaft is not connected with the inputshaft or the output shaft.
 4. The planetary gear train of claim 3,wherein the first planetary gear set is configured to be locked-up byselectively connecting any two shafts among the first shaft, the thirdshaft, and the fifth shaft with each other through any one clutch amongthe three clutches.
 5. The planetary gear train of claim 2, wherein thesix engaging elements comprise: a first clutch disposed between thesecond shaft and the sixth shaft; a second clutch disposed between thefirst shaft and the fifth shaft; a third clutch disposed between thethird shaft and the sixth shaft; a first brake disposed between theseventh shaft and the transmission housing; a second brake disposedbetween the eighth shaft and the transmission housing; and a third brakedisposed between the ninth shaft and the transmission housing.
 6. Theplanetary gear train of claim 2, wherein the six engaging elementscomprise: a first clutch disposed between the second shaft and the sixthshaft; a second clutch disposed between the first shaft and the thirdshaft; a third clutch disposed between the third shaft and the sixthshaft; a first brake disposed between the seventh shaft and thetransmission housing; a second brake disposed between the eighth shaftand the transmission housing; and a third brake disposed between theninth shaft and the transmission housing.
 7. The planetary gear train ofclaim 2, wherein the six engaging elements comprise: a first clutchdisposed between the second shaft and the sixth shaft; a second clutchdisposed between the third shaft and the fifth shaft; a third clutchdisposed between the third shaft and the sixth shaft; a first brakedisposed between the seventh shaft and the transmission housing; asecond brake disposed between the eighth shaft and the transmissionhousing; and a third brake disposed between the ninth shaft and thetransmission housing.
 8. The planetary gear train of claim 1, whereinthe first, second, and third rotational elements are a first sun gear, afirst planet carrier, and a first ring gear respectively, the fourth,fifth, and sixth rotational elements are a second sun gear, a secondplanet carrier, and a second ring gear respectively, the seventh,eighth, and ninth rotational elements are a third sun gear, a thirdplanet carrier, and a third ring gear respectively, the tenth, eleventh,and twelfth rotational elements are a fourth sun gear, a fourth planetcarrier, and a fourth ring gear respectively, and the thirteenth,fourteenth, and fifteenth rotational elements are a fifth sun gear, afifth planet carrier, and a fifth ring gear respectively.
 9. Theplanetary gear train of claim 1, wherein the first, second, third,fourth, and fifth planetary gear sets are disposed in a sequence of thefirst, third, fourth, second, and fifth planetary gear sets.
 10. Aplanetary gear train of an automatic transmission for a vehicle, theplanetary gear train comprising: an input shaft configured to receive atorque from an engine; an output shaft configured to output a torque; afirst planetary gear set including first, second, and third rotationelements; a second planetary gear set including fourth, fifth, and sixthrotation elements; a third planetary gear set including seventh, eighth,and ninth rotation elements; a fourth planetary gear set includingtenth, eleventh, and twelfth rotation elements; a fifth planetary gearset including thirteenth, fourteenth, and fifteenth rotational elements;a first shaft connected with the second rotation element and the inputshaft; a second shaft connected with the fourteenth rotation element andthe output shaft; a third shaft connected with the third rotationelement and the thirteenth rotation element; a fourth shaft connectedwith the sixth rotation element and the fifteenth rotation element; afifth shaft connected with the first rotation element, the eighthrotation element, and the twelfth rotation element; a sixth shaftconnected with the fourth rotation element and the ninth rotationelement; and a plurality of shafts configured to selectively andrespectively connect a transmission housing to corresponding rotationelements selected from the rotation elements selected from the second,third, and fourth planetary gear sets, wherein the selectedcorresponding rotation elements are not connected to any of the first tosixth shafts.
 11. The planetary gear train of claim 10, wherein theplurality of shafts comprise: a seventh shaft connected with the fifthrotation element and the eleventh rotation element; an eighth shaftconnected with the seventh rotation element; and a ninth shaft connectedwith the tenth rotation element.
 12. The planetary gear train of claim11, further comprising: three clutches, any one thereof configured toconnect any two shafts among the nine shafts; and three brakes, any onethereof configured to selectively connect the transmission housing to acorresponding shaft selected from the nine shafts, wherein the selectedcorresponding shaft is not connected with the input shaft or the outputshaft.
 13. The planetary gear train of claim 12, wherein the threeclutches comprise: a first clutch disposed between the second shaft andthe sixth shaft; a second clutch disposed between the first shaft andthe fifth shaft; and a third clutch disposed between the third shaft andthe sixth shaft, and and wherein the three brakes comprise: a firstbrake disposed between the seventh shaft and the transmission housing; asecond brake disposed between the eighth shaft and the transmissionhousing; and a third brake disposed between the ninth shaft and thetransmission housing.
 14. The planetary gear train of claim 12, whereinthe three clutches comprise: a first clutch disposed between the secondshaft and the sixth shaft; a second clutch disposed between the firstshaft and the third shaft; and a third clutch disposed between the thirdshaft and the sixth shaft, and wherein the three brakes comprise: afirst brake disposed between the seventh shaft and the transmissionhousing; a second brake disposed between the eighth shaft and thetransmission housing; and a third brake disposed between the ninth shaftand the transmission housing.
 15. The planetary gear train of claim 12,wherein the three clutches comprise: a first clutch disposed between thesecond shaft and the sixth shaft; a second clutch disposed between thethird shaft and the fifth shaft; and a third clutch disposed between thethird shaft and the sixth shaft, and wherein the three brakes comprise:a first brake disposed between the seventh shaft and the transmissionhousing; a second brake disposed between the eighth shaft and thetransmission housing; and a third brake disposed between the ninth shaftand the transmission housing.
 16. A planetary gear train of an automatictransmission for a vehicle, the planetary gear train comprising: aninput shaft configured to receive a torque from an engine; an outputshaft configured to output a torque; a first planetary gear setincluding first, second, and third rotation elements; a second planetarygear set including fourth, fifth, and sixth rotation elements; a thirdplanetary gear set including seventh, eighth, and ninth rotationelements; a fourth planetary gear set including tenth, eleventh, andtwelfth rotation elements; a fifth planetary gear set includingthirteenth, fourteenth, and fifteenth rotational elements; a first shaftconnected with the second rotation element and the input shaft; a secondshaft connected with the fourteenth rotation element and the outputshaft; a third shaft connected with the third rotation element and thethirteenth rotation element; a fourth shaft connected with the sixthrotation element and the fifteenth rotation element; a fifth shaftconnected with the first rotation element, the eighth rotation element,and the twelfth rotation element; a sixth shaft connected with thefourth rotation element and the ninth rotation element; and seventh,eighth, and ninth shafts configured to selectively and respectivelyconnect a transmission housing to corresponding rotation elementsselected from the rotation elements of the second, third, and fourthplanetary gear sets, wherein the corresponding rotation elements are notconnected to any one of the first to sixth shafts.
 17. The planetarygear train of claim 16, wherein the second shaft and the sixth shaft,the first shaft and the fifth shaft, and the third shaft and the sixthshaft are selectively and respectively connected with each other throughclutches, the seventh shaft is connected with the fifth rotation elementand the eleventh rotation element, the eighth shaft is connected withthe seventh rotation element, and the ninth shaft is connected with thetenth rotation element.
 18. The planetary gear train of claim 16,wherein the second shaft and the sixth shaft, the first shaft and thethird shaft, and the third shaft and the sixth shaft are selectively andrespectively connected with each other through clutches, the seventhshaft is connected with the fifth rotation element and the eleventhrotation element, the eighth shaft is connected with the seventhrotation element, and the ninth shaft is connected with the tenthrotation element.
 19. The planetary gear train of claim 16, wherein thesecond shaft and the sixth shaft, the third shaft and the fifth shaft,and the third shaft and the sixth shaft are selectively and respectivelyconnected with each other through clutches, the seventh shaft isconnected with the fifth rotation element and the eleventh rotationelement, the eighth shaft is connected with the seventh rotationelement, and the ninth shaft is connected with the tenth rotationelement.
 20. The planetary gear train of claim 16, wherein the first,second, and third rotational elements are a first sun gear, a firstplanet carrier, and a first ring gear respectively, the fourth, fifth,and sixth rotational elements are a second sun gear, a second planetcarrier, and a second ring gear respectively, the seventh, eighth, andninth rotational elements are a third sun gear, a third planet carrier,and a third ring gear respectively, the tenth, eleventh, and twelfthrotational elements are a fourth sun gear, a fourth planet carrier, anda fourth ring gear respectively, and the thirteenth, fourteenth, andfifteenth rotational elements are a fifth sun gear, a fifth planetcarrier, and a fifth ring gear respectively.